Phison is showing off its latest PCIe Gen 5 SSD controller chip known as the E26 (opens in new tab) at CES, including access to a fully functional demo drive. Apart from peak performance gains of over 10GB/s for both reads and writes, the big news for gamers is proper support for Microsoft's DirectStorage technology.

DirectStorage is designed to speed up in-game storage performance and make loading levels and streaming in-game content faster.

As we reported last year (open in new tab), 5th generation SSDs have already expired. So it is good to see that Phison, perhaps the largest supplier of third-party controller chips to the SSD industry, is promoting 5th generation technology with its E26 controller chip.

The engineered drive Phison is showing off is a bit limited by the NAND flash used; the Micron 232L NAND is clocked at 1600 MT/s, well below the 2400 MT/s the chip can support. So peak throughput of about 10GB/s for both reads and writes is far from the 14GB/s that will eventually be seen in Gen 5 drives (according to Phison, the E26's top speed is 14GB/s for reads and 11.8GB/s for writes).

But arguably more important on a day-to-day basis are other performance areas. One is 4K random access. Spec-wise, the E26 delivers 1.5M read IOPS and 2M write IOPS, which is a massive but not insignificant improvement over existing PCIe Gen 4 controllers.

In its own internal benchmarks, Phison claims 100MB/s for 4K QD1 reads and over 400MB/s for writes. The latter is especially impressive compared to the best Gen 4 drives, which fall below 300MB/s. 4K reads are a bit disappointing compared to the approximate 80MB/s of the Gen 4 drives. It is also worth remembering that Intel's Optane P5800X, which has sadly passed away, offers 400 MB/sec 4K read/write on the PCIe Gen 4 interface.

Another piece of the puzzle is the aforementioned DirectStorage technology. Simply put, DirectStorage moves the decompression of game data from the CPU to the GPU, simplifying and accelerating the process of loading graphics textures and other data from the SSD. According to Microsoft, game level load times are improved by 40% (opens in new tab) DirectStorage frees up CPU resources for actual gameplay, allowing game levels to load seamlessly in the background during gameplay

Phison.

Phison states that the E26's I/O+ technology was specifically designed with DirectStorage in mind. To see how much of an advantage it brings, Microsoft has developed a synthetic benchmark to test DirectStorage; known as Expanse, it tests texture streaming. According to early results (open in new tab), the E26 engineering drive provides more than 7.5 GB/s of texture streaming bandwidth. The fastest Gen 4 drive, the Sabrent Rocket 4 Plus, records 7GB/sec, while the WD SN850X records 6.3GB/sec.

Exactly how much of a difference all of this makes in gaming performance has yet to be determined. It is also likely that the performance of 5th generation drives will improve dramatically over time. Therefore, this initial view on the performance of 5th generation drives is not conclusive. [But with both Intel and AMD platforms now supporting PCIe Gen 5, it is good to see SSDs, the other half of the equation, approaching real availability, even if Phison has not given an exact date for when we will see the first drives. That's a good thing, given that Phison itself is not selling the drives, and this part is not under Phison's control.